Sofa



FIG. 1 is a front elevational view of the sofa of the present design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a bottom plan view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a side elevational view thereof; and,

FIG. 6 is a perspective view thereof in a disassembled state.

The broken lines in the drawings illustrate portions of the sofa that form no part of the claimed design. 

CLAIM The ornamental design for a sofa, as shown and described. 